Methods, Network Nodes, Computer Programs and Computer Program Products for Managing Processing of an Audio Stream

ABSTRACT

A method and a first node ( 110 ) for managing processing of an audio stream as well as a method and a second node ( 120 ) for enabling management, by a first node ( 110 ), of processing of an audio stream and corresponding computer programs and computer program products are disclosed. The audio stream is receivable from the second node ( 120 ). The first node ( 110 ) sends ( 204, 205 ), to the second node ( 120 ), information relating to at least one preference concerning acoustic characteristics of the audio stream. The second node ( 120 ) processes ( 208 ) the audio stream in response to the information relating to the at least one preference concerning the acoustic characteristics. The second node ( 120 ) transmits ( 209 ) the audio stream to the first node ( 110 ).

TECHNICAL FIELD

Embodiments herein relate to audio communication within wiredcommunication systems and wireless communication systems, such astelecommunication systems. A method and a first node for managingprocessing of an audio stream as well as a method and a second node forenabling management, by a first node, of processing of an audio streamand corresponding computer programs and computer program products aredisclosed.

BACKGROUND

Audio communication, or speech communication, is defined by manydifferent standards and can be using in different networks such asPublic Switched Telephone Networks (PSTN), second and third generationof telecommunication systems (2G and 3G systems), Third GenerationPartnership Project (3GPP TS 24.173) over High Speed Packet Access,Fourth Generation (4G) using Voice over Long Term Evolution (VoLTE)speech and audio communication, Voice over Internet Protocol (VoIP)communications.

In audio communication, an audio signal is picked up, or captured, by amicrophone, amplified to a desired level, filtered, digitally sampled,processed to remove acoustic echo, compensate for electrical andmechanical acoustic characteristic response, or reduce backgroundnoises. Then, the signal is encoded to reduce the bitrate oncetransmitted over the transmission channel, generally a radio channel ora wire, before the signal is received by a distant terminal andprocessed and played back over an earpiece, headset or loudspeaker.

During play back, it has been found that users have personal preferenceswhen it comes to noise suppression levels. For example, some personslike to have a minimum of background noise when listening to otherpeople, even if the noise suppression algorithm affects the speechquality with clipping and codec artifacts and sound distortion. Someother people like to have a little noise in the background. For example,with a little noise in the background, it may be avoided that there iscomplete silence when a distant person is not talking. Such completesilence may give the listening user the impression that communication isbroken. Some other people do like to have all the background noiseinformation so they understand the context of the other person andexperience no artifacts nor clipping on the speech.

The user's preference for the noise suppression level may also bedifferent in different situations. For example, when user A is callinguser B who is attending a football game, then user A may want littlenoise suppression to get a better experience of the atmosphere at thestadium. Another example is when user A is calling user B who is in avery noisy factory. In this case, the intelligibility of speech of userB may be very poor due to a high noise level from activities in thefactory.

It has also been observed that the user's preference is biased by thecultural environment of the user, E.g. US mobile operators seem to favoraggressive noise suppression. This may mean that for each individualuser there may be an individual preference of when the noise suppressionis perceived as optimal in that particular user's point of view.Typically, a quality of the audio, as perceived by a particular user,increases with increasingly more aggressive noise suppression. However,at some point, there will be cuts, or interruptions in the audio. Then,the particular user will consider the quality of the audio to decrease.

Similarly to how quality of audio varies with noise suppression level,quality of audio varies with audio bandwidth and speech level. Users, inparticular when elderly and slightly hearing impaired, find it moreintelligible when the speech signal is within certain frequency limitsand has certain levels. However, recent advances in terminal acousticsand speech coding, e.g. Adaptive Multi-Rate Wideband (AMR-WB), allow forlarger audio bandwidths to be represented.

In order to adopt the audio to the user's preference, it has beenproposed to apply the user's preference to the audio before the audio isplayed back to the user. WO2009/113926 discloses a known solution forproviding selective control of buffering of at least one media stream.According to the known solution, a communication device includes ajitter buffer and a jitter buffer control unit. The jitter buffercontrol unit set a buffer strategy based on an instruction, originatingfrom a user input. Then, a data stream is received and buffered, in thejitter buffer, based on the buffer strategy. In relation to for examplethe above noted individual or cultural user preferences, a disadvantageof the known solution may be that the user nevertheless sometimes isdissatisfied with the perceived quality of the data stream.

SUMMARY

An object is to enable improved user experience in for example systemscomprising communication devices of the above mentioned kinds.

According to an aspect, the object is achieved by a method, performed bya first node, for managing processing of an audio stream. The audiostream is receivable from a second node. The first node sends, to thesecond node, information relating to at least one preference concerningacoustic characteristics of the audio stream. The first node receivesthe audio stream from the second node. The audio stream has beenprocessed, by the second node, in response to the information relatingto the at least one preference concerning the acoustic characteristicsof the audio stream.

According to another aspect, the object is achieved by a first nodeconfigured to manage processing of an audio stream. The audio stream isreceivable from a second node. The first node comprises a processingcircuit configured to send, to the second node, information relating toat least one preference concerning acoustic characteristics of the audiostream. Moreover, the processing circuit is configured to receive theaudio stream from the second node. The audio stream has been processed,by the second node, in response to the information relating to the atleast one preference concerning the acoustic characteristics of theaudio stream.

According to a further aspect, the object is achieved by a method,performed by a second node, for enabling management, by a first node, ofprocessing of an audio stream. The audio stream is transmittable to thefirst node. The second node receives, from the first node, informationrelating to at least one preference concerning acoustic characteristicsof the audio stream. The second node processes the audio stream inresponse to the information relating to the at least one preferenceconcerning the acoustic characteristics. The second node transmits theaudio stream to the first node.

According to yet another aspect, the object is achieved by a second nodeconfigured to enable management, by a first node, of processing of anaudio stream. The audio stream is transmittable to the first node. Thesecond node comprises a processing circuit configured to receive, fromthe first node, information relating to at least one preferenceconcerning acoustic characteristics of the audio stream. Moreover, theprocessing circuit is configured to process the audio stream in responseto the information relating to the at least one preference concerningthe acoustic characteristics. Furthermore, the processing circuit isconfigured to transmit the audio stream to the first node.

According to a still other aspect, the object is achieved by a computerprogram for managing processing of an audio stream. The audio stream isreceivable from a second node. The computer program comprises computerreadable code units which when executed on a first node causes the firstnode to send, to the second node, information relating to at least onepreference concerning acoustic characteristics of the audio stream.Moreover, the computer program enables the first node to receive theaudio stream from the second node. The audio stream has been processed,by the second node, in response to the information relating to the atleast one preference concerning the acoustic characteristics of theaudio stream.

According to a still further aspect, the object is achieved by acomputer program product, comprising computer readable medium and acomputer program, as described above, stored on the computer readablemedium.

According to an additional aspect, the object is achieved by a computerprogram for enabling management, by a first node, of processing of anaudio stream. The audio stream is transmittable by a second node. Thecomputer program comprises computer readable code units which whenexecuted on the second node causes the second node to receive, from thefirst node, information relating to at least one preference concerningacoustic characteristics of the audio stream. Moreover, the second nodeis caused to, when the computer program is executed on the second node,process the audio stream in response to the information relating to theat least one preference concerning the acoustic characteristics.Furthermore, the second node is caused to, when the computer program isexecuted on the second node, transmit the audio stream to the firstnode.

According to a further aspect, the object is achieved by a computerprogram product, comprising computer readable medium and a computerprogram, as described above, stored on the computer readable medium.

As an example the information relating to at least one preferenceconcerning acoustic characteristics of the audio stream may beinformation about preference settings. Hence, the first node sends theinformation about preference settings to the second node. In thismanner, the second node is made aware of the preference settings. Thepreference settings may then completely or partially be applied by thesecond node when processing the audio stream. The processing of theaudio stream may be performed before the audio stream is encoded using acodec technique, such as AMR-WB or the like. Next, the audio stream istransmitted by the second node to the first node.

Furthermore, when the audio stream, represented by a speech/audioconversation session, is about to be established, or is on-going, a userof the first node may allow the second node to know what preferencesettings, the user prefers. The acoustic characteristics, e.g. thepreference settings, may be a level for suppression of noise in theaudio stream, a level of speech in the audio stream, a bandwidth of theaudio stream. Subsequently, the second node applies, as far as possible,the preference settings. As a result, the above mentioned object isachieved.

Advantageously, the received audio stream matches, at least to someextent, the at least one preference concerning acoustic characteristics.

BRIEF DESCRIPTION OF THE DRAWINGS

The various aspects of embodiments disclosed herein, includingparticular features and advantages thereof, will be readily understoodfrom the following detailed description and the accompanying drawings,in which:

FIG. 1 is a schematic overview of an exemplifying radio communicationsystem in which embodiments herein may be implemented,

FIG. 2 is a schematic, combined signaling scheme and flowchartillustrating embodiments of the methods when performed in the radiocommunication system according to FIG. 1,

FIG. 3 is a flowchart illustrating embodiments of the method in thefirst node.

FIG. 4 is a block diagram illustrating embodiments of the first node.

FIG. 5 is a flowchart illustrating embodiments of the method in thesecond node,

FIG. 6 is a block diagram illustrating embodiments of the second node,

FIG. 7 is a block diagram illustrating a computer program product and acomputer program for the first node, and

FIG. 8 is a block diagram illustrating a computer program product and acomputer program for the second node.

DETAILED DESCRIPTION

Throughout the following description similar reference numerals havebeen used to denote similar elements, units, modules, circuits, nodes,parts, items or features, when applicable. In the Figures, features thatappear in some embodiments are indicated by dashed lines.

FIG. 1 depicts an exemplifying radio communications system 100 in whichembodiments herein may be implemented. In this example, the radiocommunications system 100 is a Long Term Evolution (LTE) system. Inother examples, the radio communication system may be any 3GPP cellularcommunication system, such as a Wideband Code Division Multiple Access(WCDMA) network, a Global System for Mobile communication (GSM network)or the like. The embodiments herein may also be implemented in variouswired communication systems.

The radio communication system 100 comprises a first node 110 and asecond node 120. The first node 110 may be a user equipment and thesecond node 120 may be another user equipment 130 or a media gateway140, such as a Media Gateway processing Function (MGF) while usingterminology from the field of audio communication. In other examples,the first node 110 may be a first network node and the second node 120may be a second network node.

As used herein, the term ‘user equipment’ may refer to a mobile phone, acellular phone, a Personal Digital Assistant (PDA) equipped with radiocommunication capabilities, a smartphone, a laptop or personal computer(PC) equipped with an internal or external mobile broadband modem, atablet PC with radio communication capabilities, a portable electronicradio communication device, a fixed VoIP phone or the like.

As used herein, the term “network node” may preferably refer to a mediagateway node, but sometimes the term may refer to a base station, aradio network node, a radio network controller, a base stationcontroller, a radio network node or the like.

In some examples, a first user may use the first node 110 and a seconduser may use the second node 120.

FIG. 2 illustrates an exemplifying method according to embodimentsherein when implemented in the radio communication system 100 of FIG. 1.Thus, the first node 110 performs a method for managing processing of anaudio stream and the second node 120 performs a method for enablingmanagement, by the first node 110, of processing of the audio stream.The audio stream is transmittable to the first node 110. The audiostream may typically carry speech from a user of the second node 120.However, the audio stream may also, or instead, carry audio representingmusic, audio corresponding to a movie or the like.

Initially, before the actions 201 to 211 are performed, a session fortransfer of an audio stream from the second node 120 to the first node110 may be about to be set up. This is described in more detail insection “signalling at session set up” below.

Alternatively, a session for transfer of an audio stream from the secondnode 120 to the first node 110 is already on-going. This is described inmore detail in section “signalling during a session” below. In casethere is an on-going session, action 201 may be performed since thefirst node 110 currently receives (action not shown) an audio streamfrom the second node 120.

The following actions may be performed in any suitable order.

Action 201

The first node 110 may output audio generated from an audio streamreceived (as mentioned action not shown) from the second node 120. Thismeans that the audio may be generated from an audio stream receivedduring an already on-going session. Thanks to that the first node 110may output the audio, a user of the first node 110 may listen to theaudio. In this context, output of audio may mean that the audio isoutput to, e.g. a speaker of the first node 110 or headphones connectedto the first node 110.

Action 202

In some first embodiments, the second node 120 may suggest preferencesconcerning acoustic characteristics to apply by itself. As an example,the second user may thus suggest some preferences to the first user,which then selects from the suggested preferences. It may be that thesecond user selects the suggested preferences from a list, displayed ina user interface of the second node 120. This list may only displayavailable preferences, i.e. those preferences that may be supported bythe second node 120. The selected preference may then be sent in action204. Alternatively, predefined or preferences stored in the second node120 may be sent in this action 202.

Hence, in order to suggest preferences, the second node 120 may send, tothe first node 110, a message indicating at least one preferenceconcerning the acoustic characteristics to be applied, at least partly,by the second node 120 when processing the audio stream in action 208.This message is referred to as a first message herein.

Action 203

Accordingly subsequent to action 202, in the first embodiments, thefirst node 110 may receive, from the second node 120, the first message.

Action 204

In order for the second node 120 to be aware of which preferenceconcerning acoustic characteristics, the first node 110 sends, to thesecond node 120, information relating to at least one preferenceconcerning acoustic characteristics of the audio stream.

The at least one preference concerning acoustic characteristics mayrelate to one or more of:

-   -   a level for suppression of noise in the audio stream,    -   a level of speech in the audio stream,    -   a bandwidth of the audio stream, and    -   the like.

The level of suppression of noise in the audio stream, or a noisesuppression level for short. Merely as an example, “−10 dB” is a noisesuppression of 10 dB applied to noise in the audio stream.

The level of speech in the audio stream, or speech level for short,determines a default volume of the speech.

In more detail, the bandwidth of the audio stream refers to a bandwidthof audio generated from the audio stream.

The at least one preference concerning acoustic characteristics may bedetermined by a previous or current user of the first node 110. This maymean that the at least one preference may be stored in the first node110 or that a user interface may be invoked to receive the at least onepreference from the first user. Alternatively, the at least onepreference concerning acoustic characteristics may be determined by anoperator. This means that the user interface may be activated by thefirst node 110 in order to make it possible for the first node 110 toreceive, from the first user, the information relating to the at leastone preference concerning acoustic characteristics. Thus, the first node110 may include the user interface (not shown). When the operatordetermines the at least one preference, default preferences may beapplied. Default preferences may be pre-defined, or pre-determined forexample according to some average preference among some specific groupof users.

In case, a session is to be set up, the information relating to at leastone preference concerning acoustic characteristics may be comprised inat least one Session Description Protocol (SDP) parameter in a SessionInitiation Protocol (SIP) INVITE and Response message 220. In moredetail, the information may be comprised in e.g. in an SDP Offer/answermessage as part of the SIP INVITE and Response message 220.

In case, a session is already on-going, the information relating to atleast one preference concerning acoustic characteristics may becomprised in one of

at least one SDP parameter in a SIP UPDATE and Response message 220;

at least one Real-time Transport Control Protocol (RTCP) parameter; and

a Real-time Transport Protocol (RTP) header extension.

If an RTP header extension is used, the information relating to acousticcharacteristics is comprised in the RTP header extension may comprisesone or more fields for carrying the information relating to acousticcharacteristics. Said one or more fields may be defined in a relatedstandard specification like e.g. Internet Engineering Task Force (IETF)or 3GPP or in a specification of the first node. The specification ofthe first node 110 may be defined by the vendor or manufacturer of thefirst node 110.

In the first embodiments, the information relating to the at least onepreference concerning the acoustic characteristics may comprise amessage for acknowledging use of the at least one preference concerningthe acoustic characteristics indicated in the first message. Thismessage for acknowledging use may be referred to as a second messageherein. When the at least one preference concerning acousticcharacteristics is used, the second node 120 may at least partly applythe at least one preference concerning the acoustic characteristics. Forexample, the at least one preference concerning the acousticcharacteristics indicates, or comprises, a noise suppression level.Then, the second node 120 may have suggested 10 dB as noise suppressionlevel in action 202. However, the first node 110 may in some case onlyacknowledge application of e.g. 6 dB as noise, suppression level byindication in the second message. Hence, the acknowledged application ofthe at least one preference concerning acoustic characteristic may beused in action 208 below. This may mean that the second message may be ashort message stating OK or not OK or a longer message indicating OK anda value, such as 6 dB, of the acknowledged preference concerningacoustic characteristics.

It shall be understood that in some examples, the second message may notacknowledge use of the at least one preference concerning acousticcharacteristics at all. That is to say, in such examples none of the atleast one preference is applied in action 208.

In some second embodiments, the information relating to the at least onepreference concerning the acoustic characteristics may comprise amessage for instructing the second node 120 to apply the at least onepreference concerning the acoustic characteristics when processing theaudio stream. Notably, as is described by the second embodimentsincluding action 206 and 207, the second node 120 is not bound toexactly apply, in action 208, the at least one preference concerning theacoustic characteristics when processing the audio stream in action 208.The message for instructing the second node 120 may be referred to as athird message herein.

Action 205

As a consequence of action 204, the second node 120 receives, from thefirst node 110, information relating to at least one preferenceconcerning acoustic characteristics of the audio stream.

In the first embodiments, the second message is received by the secondnode 120.

In the second embodiments, the third message is received by the secondnode 120.

Action 206

According to the second embodiments, the second node 120 may send, tothe first node 110, a message indicating the at least partly applied, orto be applied in action 208, one of the at least one preferenceconcerning the acoustic characteristics. Notably, in some case themessage may indicate that none of the at least one preference concerningacoustic characteristics is, or will be, applied in action 208. Thismessage may be referred to as a fourth message herein. Therefore, thefourth message may be said to indicate none or at least one preferenceconcerning the acoustic characteristics that is, or will be applied. Itis preferred that action 206 is performed before action 209, but action206 may be performed after action 208. When action 206 is performedbefore action 209, the first node 110 may be informed about the appliedpreference concerning acoustic characteristics before the audio streamis received by the first node 110 in action 210.

Expressed somewhat differently, the fourth message is a message foracknowledging, at least in part, the third message. Hence, the secondnode 120 may confirm to the first node 110 what preference is, or willbe, applied in action 208.

As an example, the preference concerning acoustic characteristicsindicates, or comprises, a noise suppression level. Then, the thirdmessage may instruct the second node 120 to apply e.g. 10 dB as noisesuppression. However, in action 206, the fourth message may indicate 8dB as noise suppression level actually applied. Thanks to that the firstnode 110 may know the applied noise suppression level, i.e. 8 dB, it mayrefrain from once again requesting 10 dB as noise suppression in asubsequent message to the second node 120.

Action 207

In the second embodiments, the first node 110 may receive, from thesecond node 120, the fourth message.

Action 208

The second node 120 processes the audio stream in response to theinformation relating to the at least one preference concerning theacoustic characteristics.

In the first embodiments, the second node 120 processes the audio streamaccording to the second message. In this case, the first node 110 mayknow that the second node 120 will apply the acknowledged application ofthe at least one preference concerning acoustic characteristics sincethe preference concerning acoustic characteristics was, at least partly,suggested by the second node 120. It will be assumed that the secondnode 120 may not suggest preference concerning acoustic characteristicsthat it is not able to apply in this action 208.

In the second embodiments, the second node 120 processes the audiostream in response to the third message. In this case, the second node120 may completely or partly process the audio stream according to thethird message. As an example as mentioned above, the third message mayindicate 12 dB as noise suppression, while the second node 120 only isable to, or allowed to, apply 8 dB as noise suppression.

For noise suppression, it is nowadays common to apply dual- or multimicrophone technologies which have the potential of greatly improvingthe noise suppression performance. In these scenarios, it is requiredthat the processing is applied by the second node 120 which transmitsthe audio stream in action 209.

For the level of speech in the audio stream and the bandwidth of theaudio stream, an advantage of applying one or more of these preferencesin the second node 120 is that the audio stream to be transmitted may bemore efficiently encoded, using for example AMR-WB. A reason to thatcoding is more efficient may be that amount of information carried inthe audio stream may be reduced when applying one or more of the levelof speech in the audio stream and the bandwidth of the audio stream orthat coding range may be more efficiently used.

In this context, it deserves to be mentioned that the preferenceconcerning acoustic characteristics does not include parameterscontrolling the coding, using for example AMR-WB or the like. Forexample, a Change Mode Request (CMR) concerning bit rate for theencoding is not an acoustic characteristic.

Hence, after the processing in action 209, but before action 209 below,the second node 120 may encode the audio stream using for example AMR-WBor the like.

Action 209

The second node 120 transmits 209 the audio stream, as processed inaction 208, to the first node 110. That is to say, a processed audiostream is transmitted to the first node 110.

Action 210

The first node 110 receives the audio stream from the second node 120.In more detail, the first node 110 received the processed audio streamfrom the second node 120.

Action 211

The first node 110 may output audio generated from the received audiostream. This action is similar to action 201, however action 211 appliesto both when a session is set up and when a session is on-going. Thanksto that the first node 110 may output the audio, a user of the firstnode 110 may listen to the audio in way that matches the preference orthe at least one preference. The preference may relate to the firstuser's preference, the second user's preference, a further user'spreference or the operator's preference depending on how the preferenceconcerning acoustic characteristics has been determined.

At this stage, after action 211, the audio may be output until thesecond node 120 stops transmission of the audio stream and any bufferfor storing the audio is empty.

Signaling at Session Setup

When the first node 110 initiates or receives a call from the secondnode 12 it is capable of sending the preference concerning acousticcharacteristics to the second node 120 during the session setup. Thiscan be achieved by e.g. adding SDP attributes and parameters indicatingthe preference, as an example of the information relating to the leastone preference concerning acoustic characteristics, under the m-line ofthe SDP file corresponding to the audio media line. E.g.:

a=Rx-acoustic-noise-suppression-level:16a=Rx-acoustic-speech-level:12a=Rx-acoustic-audio-bandwidth:300 3400

The unit of a=Rx-acoustic-noise-suppression-level:16 is in dB, it couldalso be signaled as an abstracted figure level like [0;5] with 5corresponding to a strong noise suppression and 0 to no noisesuppression at all.

The unit for a=Rx-acoustic-speech-level:12 is dBm

The unit of a=Rx-acoustic-audio-bandwidth:300 3400 is kHz.

The SDP Offer Answer model [RFC3264] is used here because the primaryembodiment applies to 3GPP Multimedia Telephony Service over IPMultimedia Subsystem (IMS) which makes use of the SDP offer/answermechanism. But any signaling mechanism used for establishment of aspeech/audio session can be extended to carry such additionalparameters.

The second node 120 receives the parameters and stores them in atemporary memory as preferred sender acoustic parameters values. Thosevalues are then used to configure procedures, relating to the level ofnoise suppression, the level of speech, the bandwidth of the audiostream, in the second node 120. The first node 110 may also implementsfunctions for storing the acoustic parameter value(s) of the second node120. Similarly, the second node 120 may implement functions for storingthe acoustic parameter value(s) of the first node 110.

Signaling During a Session

It is possible to change the acoustic parameters also during thesession. One way to do this is to perform a new SDP offer/answer forthese parameters by including them in a SIP UPDATE (or sending a new SIPINVITE, a so called “SIP re INVITE”). In this case, the procedure isexactly the same as during the session setup as described in Section6.2.

Changing the acoustic parameters using SIP UPDATE is a feasible solutionwhen the changes are rare. A drawback with using SIP is that SIPsignaling uses bearers with very high priority. Due to the high prioritythese bearers are relatively expensive, too expensive for frequentupdates.

Hence, for more frequent modifications of the acoustic parameters it isbetter to use some other protocol like RTCP or similar.

This solution is, of course, not limited to the use of SIP or RTCP.

Interworking with Legacy Equipment

In the above description it is assumed that both the first node 110,referred to as a local terminal, and the second node 120, referred to asa remote terminal, support this functionality and signaling. Byimplementing this solution in the media gateway 140, some parts of thefunctionality can be achieved also when the remote terminal is a legacyphone either that does not support this functionality and signaling, orwhen it performs a fixed amount. For example, if the desired totalamount of noise suppression is 16 dB, then this can be achieved inseveral ways:

-   -   The legacy terminal performs no noise suppression and the media        gateway 140 reduces the noise by 16 dB.    -   Or the legacy terminal performs 5 dB of noise suppression and        the media gateway 140 reduces the noise by another 11 dB.    -   Or the legacy terminal performs 12 dB of noise suppression and        the media gateway 140 reduces the noise by another 4 dB.

However, if the legacy terminal has already performed 20 dB of noisesuppression then the media gateway 140 cannot increase the noise levelsince it does not know what noise to inject.

In FIG. 3, an exemplifying, schematic flowchart of the method in thefirst node 110 is shown. As mentioned, the first node 110 performs amethod for managing processing of an audio stream. The audio stream isreceivable from a second node 120.

The following actions may be performed in any suitable order.

State 300

In a start state 300 before the actions 301 to 306 are performed, thefirst node 110 may be about to set up a session for transfer of theaudio stream from the second node 120 to the first node 110. See alsosection “signaling at session set up” above.

Alternatively, the first node 110 may in a start state 300 already haveset up a session for transfer of the audio stream from the second node120 to the first node 110. Thus, in this case action 301 may beperformed since the first node 110 currently receives an audio stream(action not shown). See also section “signaling during a session” above.

Action 301

The first node 110 may output audio generated from the received audiostream. This action is similar to action 201.

Action 302

The first node 110 may receive, from the second node 120, a messageindicating at least one preference concerning the acousticcharacteristics to be applied by the second node 120 when processing theaudio stream. The information relating to the at least one preferenceconcerning the acoustic characteristics may comprise a message foracknowledging, at least partly, application, by the second node 120, ofthe at least one preference concerning the acoustic characteristicsindicated in the received message indicating the at least one preferenceconcerning the acoustic characteristics. This action is similar toaction 203.

Action 303

The first node 110 sends, to the second node 120, information relatingto at least one preference concerning acoustic characteristics of theaudio stream. This action is similar to 204.

As mentioned, the at least one preference concerning acousticcharacteristics may relate to one or more of:

-   -   a level for suppression of noise in the audio stream,    -   a level of speech in the audio stream,    -   a bandwidth of the audio stream, and    -   the like.

Again, the at least one preference concerning acoustic characteristicsmay be determined by a previous or current user of the first node 110.Alternatively, the at least one preference concerning acousticcharacteristics may be determined by an operator of a radiocommunication system 100 comprising the first and second nodes 110, 120.

As mentioned, the information relating to at least one preferenceconcerning acoustic characteristics may be comprised in one of:

at least one SDP parameter in a SIP INVITE and Response message;

at least one SDP parameter in a SIP UPDATE and Response message;

at least one RTCP parameter; and

an RTP header extension.

Action 304

The information relating to the at least one preference concerning theacoustic characteristics may comprise a message for instructing thesecond node 120 to apply the at least one preference concerning theacoustic characteristics when processing the audio stream.

Then, the first node 110 may receive, from the second node 120, amessage indicating one of the at least one preference concerning theacoustic characteristics. Said one of the at least one preferenceconcerning the acoustic characteristics will be at least partly appliedby the second node 120 when processing the audio stream. This action issimilar to action 207.

Action 305

The first node 110 receives the audio stream from the second node 120.The audio stream has been processed, by the second node 120, in responseto the information relating to the at least one preference concerningthe acoustic characteristics of the audio stream. This action is similarto action 210.

Action 306

The first node 110 may output audio generated from the received audiostream. This action is similar to action 211.

State 307

In an end state 307, the first node 110 may continue to receive andoutput the audio stream, if the second node 120 continues transmissionof the audio stream, as in action 209 above, or if any buffer forstoring of the audio stream is not yet empty. Output, in action 306, ofaudio will be possible as long as said any buffer is not yet empty.

Alternatively, the first node 110 may in an end state 307 no longerreceive or output audio, if the second node 120 stops transmission ofthe audio stream, or if any buffer for storing the audio is empty.

With reference to FIG. 4, a schematic block diagram of the first node110 is shown. The first node 110 is configured to perform the methods inFIGS. 2 and/or 3. Thus, the first node 110 is configured to manageprocessing of an audio stream. As mentioned, the audio stream isreceivable from a second node 120.

The first node 110 comprises a processing circuit 410 configured tosend, to the second node 120, information relating to at least onepreference concerning acoustic characteristics of the audio stream.

As mentioned, the at least one preference concerning acousticcharacteristics may relate to one or more of:

-   -   a level for suppression of noise in the audio stream,    -   a level of speech in the audio stream,    -   a bandwidth of the audio stream, and    -   the like.

Again, the at least one preference concerning acoustic characteristicsmay be determined by a previous or current user of the first node 110.Alternatively, the at least one preference concerning acousticcharacteristics may be determined by an operator of a radiocommunication system 100 comprising the first and second nodes 110, 120.

As mentioned, the information relating to at least one preferenceconcerning acoustic characteristics may be comprised in one of:

at least one SDP parameter in a SIP INVITE and Response message;

at least one SDP parameter in a SIP UPDATE and Response message;

at least one RTCP parameter; and

an RTP header extension.

Moreover, the processing circuit 410 is configured to receive the audiostream from the second node 120. The audio stream has been processed, bythe second node 120, in response to the information relating to the atleast one preference concerning the acoustic characteristics of theaudio stream.

According to the first embodiments, the processing circuit 410 mayfurther be configured to receive, from the second node 120, a messageindicating at least one preference concerning the acousticcharacteristics to be applied by the second node 120 when processing theaudio stream. In these embodiments, the information relating to the atleast one preference concerning the acoustic characteristics maycomprise a message for acknowledging, at least partly application, bythe second node 120, of the at least one preference concerning theacoustic characteristics indicated in the received message indicatingthe at least one preference concerning the acoustic characteristics.

According to the second embodiments, the information relating to the atleast one preference concerning the acoustic characteristics maycomprise a message for instructing the second node 120 to apply the atleast one preference concerning the acoustic characteristics whenprocessing the audio stream. In these embodiments, the processingcircuit 410 may further be configured to receive, from the second node120, a message indicating one of the at least one preference concerningthe acoustic characteristics. Said one of the at least one preferenceconcerning the acoustic characteristics will be at least partly appliedby the second node 120 when processing the audio stream.

The processing circuit 410 may further be configured to output audiogenerated from the received audio stream.

The first node 110 may further comprise a transmitter 420, which may beconfigured to send the information relating to at least one preferenceconcerning acoustic characteristics and other numbers, values orparameters described herein.

The first node 110 may further comprise a receiver 430, which may beconfigured to receive the message(s) and other numbers, values orparameters described herein.

The first node 110 further comprises a memory 440 for storing softwareto be executed by, for example, the processing circuit. The software maycomprise instructions to enable the processing circuit to perform themethod in the first node 110 as described above in conjunction withFIGS. 2 and/or 3.

In FIG. 5, an exemplifying, schematic flowchart of the method in thesecond node 120 is shown. As mentioned, the second node 120 performs amethod for enabling management, by a first node 110, of processing of anaudio stream. The audio stream is transmittable to the first node 110.

The following actions may be performed in any suitable order.

State 500

In a start state 500 before the actions 501 to 505 are performed, thesecond node 120 may be about to transfer an audio stream to the firstnode 110. See also section “signalling at session set up” above.

Alternatively, the second node 120 may in a start state 500 already beinvolved in a session for transfer of the audio stream to the first node110. Thus, the second node 120 already sends (action not shown) an audiostream to the first node 110. See also section “signalling during asession” above.

Action 501

The second node 120 may send, to the first node 110, a messageindicating at least one preference concerning the acousticcharacteristics to be applied by the second node 120 when processing theaudio stream.

The information relating to the at least one preference concerning theacoustic characteristics may comprise a message for acknowledging, atleast partly, application, by the second node 120, of the at least onepreference concerning the acoustic characteristics indicated in thereceived message indicating the at least one preference concerning theacoustic characteristics. The processing of the audio stream maycomprise applying, at least as partly acknowledged, the at least onepreference concerning the acoustic characteristics. This action issimilar to action 202.

Action 502

The second node 120 receives 205, from the first node 110, informationrelating to at least one preference concerning acoustic characteristicsof the audio stream. This action is similar to action 205.

As mentioned, the at least one preference concerning acousticcharacteristics may relate to one or more of:

-   -   a level for suppression of noise in the audio stream,    -   a level of speech in the audio stream,    -   a bandwidth of the audio stream, and    -   the like.

Again, the at least one preference concerning acoustic characteristicsmay be determined by a previous or current user of the first node 110.Alternatively, the at least one preference concerning acousticcharacteristics may be determined by an operator of a radiocommunication system 100 comprising the first and second nodes 110, 120.

As mentioned, the information relating to at least one preferenceconcerning acoustic characteristics may be comprised in one of:

at least one SDP parameter in a SIP INVITE and Response message;

at least one SDP parameter in a SIP UPDATE and Response message;

at least one RTCP parameter; and

an RTP header extension.

Action 503

The information relating to the at least one preference concerning theacoustic characteristics may comprise a message for instructing thesecond node 120 to apply the at least one preference concerning theacoustic characteristics when processing the audio stream. Theprocessing of the audio stream comprises applying, at least partly, oneof the at least one preference concerning the acoustic characteristics.

The second node 120 may send, to the first node 110, a messageindicating the at least partly applied one of the at least onepreference concerning the acoustic characteristics. This action issimilar to action 206.

Action 504

The second node 120 processes the audio stream in response to theinformation relating to the at least one preference concerning theacoustic characteristics. This action is similar to action 208.

Action 505

The second node 120 transmits the audio stream to the first node 110.This action is similar to action 209.

State 506

In an end state 506, the second node 120 may continue transmission ofthe audio stream, as in action 209 above.

Alternatively, the second node 120 may in an end state 506 stoptransmission of the audio stream.

In FIG. 6, a schematic block diagram of the second node 120 is shown.The second node 120 is configured to perform the methods in FIGS. 2and/or 5. Thus, the second node 120 is configured to enable management,by a first node 110, of processing of an audio stream. As mentioned, theaudio stream is transmittable to the first node 110.

The second node 120 comprises a processing circuit 810 configured toreceive, from the first node 110, information relating to at least onepreference concerning acoustic characteristics of the audio stream.Moreover, the processing circuit 610 is configured to process the audiostream in response to the information relating to the at least onepreference concerning the acoustic characteristics. Furthermore, theprocessing circuit 610 is configured to transmit the audio stream to thefirst node 110.

As mentioned, the at least one preference concerning acousticcharacteristics may relate to one or more of:

-   -   a level for suppression of noise in the audio stream,    -   a level of speech in the audio stream,    -   a bandwidth of the audio stream, and    -   the like.

Again, the at least one preference concerning acoustic characteristicsmay be determined by a previous or current user of the first node 110.Alternatively, the at least one preference concerning acousticcharacteristics may be determined by an operator of a radiocommunication system 100 comprising the first and second nodes 110, 120.

As mentioned, the information relating to at least one preferenceconcerning acoustic characteristics may be comprised in one of:

at least one SDP parameter in a SIP INVITE and Response message;

at least one SDP parameter in a SIP UPDATE and Response message;

at least one FRTCP parameter; and

an RTP header extension.

According the second embodiments, the information relating to the atleast one preference concerning the acoustic characteristics comprises amessage for instructing the second node 120 to apply the at least onepreference concerning the acoustic characteristics when processing theaudio stream. Then the processing circuit 610 further is configured toprocess the audio stream by applying, at least partly, one of the atleast one preference concerning the acoustic characteristics. Theprocessing circuit 610 may further be configured to send, to the firstnode 110, a message indicating the at least partly applied one of the atleast one preference concerning the acoustic characteristics.

According to the first embodiments, the processing circuit 610 mayfurther be configured to send, to the first node 110, a messageindicating at least one preference concerning the acousticcharacteristics to be applied by the second node 120 when processing theaudio stream. The information relating to the at least one preferenceconcerning the acoustic characteristics may comprise a message foracknowledging, at least partly, application, by the second node 120, ofthe at least one preference concerning the acoustic characteristicsindicated in the received message indicating the at least one preferenceconcerning the acoustic characteristics. Then, the processing circuit610 may further be configured to process the audio stream by applying,at least as partly acknowledged, the at least one preference concerningthe acoustic characteristics.

The second node 120 may further comprise a transmitter 620, which may beconfigured to send the message(s) and other numbers, values orparameters described herein.

The second node 120 may further comprise a receiver 630, which may beconfigured to receive the information relating to at least onepreference concerning acoustic characteristics and other numbers, valuesor parameters described herein.

The second node 120 further comprises a memory 640 for storing softwareto be executed by, for example, the processing circuit. The software maycomprise instructions to enable the processing circuit to perform themethod in the second node 120 as described above in conjunction withFIGS. 2 and/or 5.

In FIG. 7, a block diagram, representing a computer program 71 formanaging processing of an audio stream, is shown. As mentioned, theaudio stream is receivable from a second node 120. The computer program71 comprises computer readable code units which when executed on a firstnode 110 causes the first node 110 to send, to the second node 120,information relating to at least one preference concerning acousticcharacteristics of the audio stream. Moreover, the computer programenables the first node 110 to receive the audio stream from the secondnode 120. As mentioned, the audio stream has been processed, by thesecond node 120, in response to the information relating to the at leastone preference concerning the acoustic characteristics of the audiostream.

Moreover, FIG. 7 illustrates a computer program product 70, comprisingcomputer readable medium and a computer program 71. The computer program71, as described above, is stored on the computer readable medium.

In FIG. 8, a block diagram, representing a computer program 81 forenabling management, by a first node 110, of processing of an audiostream. As mentioned, the audio stream is transmittable by a second node120. The computer program 81 comprises computer readable code unitswhich when executed on the second node 120 causes the second node 120 toreceive, from the first node 110, information relating to at least onepreference concerning acoustic characteristics of the audio stream.Moreover, the second node 120 is caused to, when the computer program isexecuted on the second node 120, process the audio stream in response tothe information relating to the at least one preference concerning theacoustic characteristics. Furthermore, the second node 120 is caused to,when the computer program is executed on the second node 120, transmitthe audio stream to the first node 110.

Moreover, FIG. 8 illustrates a computer program product 80, comprisingcomputer readable medium and a computer program 81. The computer program81, as described above, is stored on the computer readable medium.

As used herein, the term “processing circuit” may be a processing unit,a processor, an application specific integrated circuit (ASIC), afield-programmable gate array (FPGA) or the like. As an example, aprocessor, an ASIC, an FPGA or the like may comprise one or moreprocessor kernels. In some examples, the processing circuit may beembodied by a software or hardware module. Any such module may be adetermining means, estimating means, calculating means, capturing means,associating means, comparing means, identification means, selectingmeans, receiving means, processing means, generating means, transmittingmeans, setting means, adjusting means, obtaining means, or the like. Asan example, the expression “means” may be a unit, such as a determiningunit, selecting unit, etc. Hence, as an example when the processingcircuit is configured to estimate a value, the processing circuit may inthat respect be replaced by an estimating unit configure to estimate avalue.

As used herein, the term “memory” may be a hard disk, a magnetic storagemedium, a portable computer diskette or disc, flash memory, randomaccess memory (RAM) or the like. Furthermore, “a memory” may be aninternal register memory of a processing circuit as described inconnection with embodiments herein.

As used herein, the expression “configured to” may be that a processingcircuit is configured to, or adapted to, by means of software orhardware configuration, perform one or more of the actions describedherein.

As used herein, the terms “number”, “value” may be any kind of digit,such as binary, real, imaginary or rational number or the like.Moreover, “number”, “value” may be one or more characters, such as aletter or a string of letters. “number”, “value” may also be representedby a bit string.

As used herein, the expression “in some embodiments” has been used toindicate that the features of the embodiment described may be combinedwith any other embodiment disclosed herein.

Even though embodiments of the various aspects have been described, manydifferent alterations, modifications and the like thereof will becomeapparent for those skilled in the art. The described embodiments aretherefore not intended to limit the scope of the present disclosure.

1-32. (canceled)
 33. A method, performed by a first node, for managing processing of an audio stream, wherein the audio stream is receivable from a second node, wherein the method comprises: sending, to the second node, information relating to at least one preference concerning acoustic characteristics of the audio stream, wherein the at least one preference concerning acoustic characteristics relates to one or more of: a level of suppression of noise in the audio stream, a level of speech in the audio stream, and a bandwidth of the audio stream, wherein the at least one preference concerning acoustic characteristics is determined by a previous or current user of the first node, or wherein the at least one preference concerning acoustic characteristics is determined by an operator of a radio communication system comprising the first and second nodes; and receiving the audio stream from the second node, wherein the audio stream has been processed, by the second node, in response to the information relating to the at least one preference concerning the acoustic characteristics of the audio stream.
 34. A method, performed by a second node, for enabling management, by a first node, of processing of an audio stream, wherein the audio stream is transmittable to the first node, wherein the method comprises: receiving, from the first node, information relating to at least one preference concerning acoustic characteristics of the audio stream, wherein the at least one preference concerning acoustic characteristics relates to one or more of: a level of suppression of noise in the audio stream, a level of speech in the audio stream, and a bandwidth of the audio stream, wherein the at least one preference concerning acoustic characteristics is determined by a previous or current user of the first node, or wherein the at least one preference concerning acoustic characteristics is determined by an operator of a radio communication system comprising the first and second nodes; processing the audio stream in response to the information relating to the at least one preference concerning the acoustic characteristics; and transmitting the audio stream to the first node.
 35. A first node configured to manage processing of an audio stream, wherein the audio stream is receivable from a second node, wherein the first node comprises a processing circuit configured to: send, to the second node, information relating to at least one preference concerning acoustic characteristics of the audio stream, wherein the at least one preference concerning acoustic characteristics relates to one or more of: a level of suppression of noise in the audio stream, a level of speech in the audio stream, and a bandwidth of the audio stream, wherein the at least one preference concerning acoustic characteristics is determined by a previous or current user of the first node, or wherein the at least one preference concerning acoustic characteristics is determined by an operator of a radio communication system comprising the first and second nodes; and receive the audio stream from the second node, wherein the audio stream has been processed, by the second node, in response to the information relating to the at least one preference concerning the acoustic characteristics of the audio stream.
 36. The first node according to claim 35, wherein the information relating to at least one preference concerning acoustic characteristics is comprised in one of: at least one Session Description Protocol (SDP) parameter in a Session Initiation Protocol (SIP) INVITE and Response message; at least one SDP parameter in a SIP UPDATE and Response message; at least one Real-Time Transport Control Protocol (RTCP) parameter; and a Real-Time Transport Protocol (RTP) header extension.
 37. The first node according to claim 35, wherein the information relating to the at least one preference concerning the acoustic characteristics comprises a message for instructing the second node to apply the at least one preference concerning the acoustic characteristics when processing the audio stream, wherein the processing circuit further is configured to: receive, from the second node, a message indicating one of the at least one preference concerning the acoustic characteristics, wherein said one of the at least one preference concerning the acoustic characteristics will be at least partly applied by the second node when processing the audio stream.
 38. The first node according to claim 35, wherein the processing circuit further is configured to: receive, from the second node, a message indicating at least one preference concerning the acoustic characteristics to be applied by the second node when processing the audio stream, wherein the information relating to the at least one preference concerning the acoustic characteristics comprises a message for acknowledging, at least partly application, by the second node, of the at least one preference concerning the acoustic characteristics indicated in the received message indicating the at least one preference concerning the acoustic characteristics.
 39. The first node according to claim 35, wherein the processing circuit further is configured to: output audio generated from the received audio stream.
 40. The first node according to claim 35, wherein the first node is a user equipment.
 41. A second node configured to enable management, by a first node, of processing of an audio stream, wherein the audio stream is transmittable to the first node, wherein the second node comprises a processing circuit configured to: receive, from the first node, information relating to at least one preference concerning acoustic characteristics of the audio stream, wherein the at least one preference concerning acoustic characteristics relates to one or more of: a level of suppression of noise in the audio stream, a level of speech in the audio stream, and a bandwidth of the audio stream, wherein the at least one preference concerning acoustic characteristics is determined by a previous or current user of the first node, or wherein the at least one preference concerning acoustic characteristics is determined by an operator of a radio communication system comprising the first and second nodes; process the audio stream in response to the information relating to the at least one preference concerning the acoustic characteristics; and transmit the audio stream to the first node.
 42. The second node according to claim 41, wherein the information relating to the at least one preference concerning the acoustic characteristics is comprised in one of: at least one Session Description Protocol (SDP) parameter in a Session Initiation Protocol (SIP) INVITE and Response message; at least one SDP parameter in a SIP UPDATE and Response message; at least one Real-Time Transport Control Protocol (RTCP) parameter; and a Real-Time Transport Protocol (RTP) header extension.
 43. The second node according to claim 41, wherein the information relating to the at least one preference concerning the acoustic characteristics comprises a message for instructing the second node to apply the at least one preference concerning the acoustic characteristics when processing the audio stream, wherein the processing circuit further is configured to process the audio stream by applying, at least partly, one of the at least one preference concerning the acoustic characteristics: and wherein the processing circuit further is configured to: send, to the first node, a message indicating the at least partly applied one of the at least one preference concerning the acoustic characteristics.
 44. The second node according to claim 41, wherein the processing circuit further is configured to: send, to the first node, a message indicating at least one preference concerning the acoustic characteristics to be applied by the second node when processing the audio stream, wherein the information relating to the at least one preference concerning the acoustic characteristics comprises a message for acknowledging, at least partly, application, by the second node, of the at least one preference concerning the acoustic characteristics indicated in the received message indicating the at least one preference concerning the acoustic characteristics, and wherein the processing circuit further is configured to process the audio stream by applying, at least as partly acknowledged, the at least one preference concerning the acoustic characteristics.
 45. The second node according to claim 41, wherein the second node is a user equipment or a media gateway.
 46. A non-transitory computer-readable medium storing a computer program comprising program instructions that, when executed by processing circuitry of a first node, configure the first node for managing processing of an audio stream, wherein the audio stream is receivable from a second node, and wherein the computer program comprises program instructions configuring the first node to: send, to the second node, information relating to at least one preference concerning acoustic characteristics of the audio stream, wherein the at least one preference concerning acoustic characteristics relates to one or more of: a level of suppression of noise in the audio stream, a level of speech in the audio stream, and a bandwidth of the audio stream, wherein the at least one preference concerning acoustic characteristics is determined by a previous or current user of the first node, or wherein the at least one preference concerning acoustic characteristics is determined by an operator of a radio communication system comprising the first and second nodes; and receive the audio stream from the second node, wherein the audio stream has been processed, by the second node, in response to the information relating to the at least one preference concerning the acoustic characteristics of the audio stream.
 47. A non-transitory computer-readable medium storing a computer program comprising program instructions that, when executed by processing circuitry of a second node, configure the second node for processing an audio stream, wherein the audio stream is transmittable by the second node to a first node, and wherein the computer program comprises program instructions configuring the second node to: receive, from the first node, information relating to at least one preference concerning acoustic characteristics of the audio stream, wherein the at least one preference concerning acoustic characteristics relates to one or more of: a level of suppression of noise in the audio stream, a level of speech in the audio stream, and a bandwidth of the audio stream, wherein the at least one preference concerning acoustic characteristics is determined by a previous or current user of the first node, or wherein the at least one preference concerning acoustic characteristics is determined by an operator of a radio communication system comprising the first and second nodes; process the audio stream in response to the information relating to the at least one preference concerning the acoustic characteristics; and transmit the audio stream to the first node. 